Thursday, August 30, 2007

Interview with Linda Bacon on weight and health

Linda Bacon
Linda Bacon is a strong advocate of the Health at Every Size movement and pleads for ending the war on obesity (don't miss her video message over there). She earned her doctorate in physiology from the University of California, Davis, specializing in weight regulation. She also holds graduate degrees in both psychology (specializing in eating disorders and body image) and exercise science (specializing in metabolism), and has professional experience as a researcher, clinical psychotherapist, exercise physiologist, and educator. In addition to serving as an Assistant Researcher in the Nutrition Department, Dr. Bacon teaches Nutrition in the Biology Department at City College of San Francisco and conducts trainings for health professionals on the latest research in weight regulation.

She has agreed to answer the tough questions of Med Journal Watch. And here we go!

Christian Bachmann: Prior to this interview you have been so kind to let me calculate your body mass index. You have the same as mine, 21. Isn't it easy to tell people that being fat is no problem when it is not your problem?

Linda Bacon: When I say that fat is not a problem, don't get me wrong - I believe that FAT STIGMA is a huge problem - for all of us. I do understand that it is extraordinarily difficult to live in the world in a stigmatized body. I'm suggesting that we fight the stigma as opposed to trying to make fat people change (get thin). When we observe racism, it just isn't valuable to encourage people of color to lighten their skin - or to tell them they're somehow wrong. The stigmatization is also wounding for people who are not fat as they have to live in fear of becoming fat.

CB: I agree. But if you were fat, I could argue that your statements were just sort of an excuse for being fat.

LB: I have frequently noticed my "thin privilege" in the world - that people often take what I say more seriously than when a fat person says the same thing. A lot of fat people have figured out the same things that I have. And their voices can be powerful also, perhaps even more so as they can be role models of living proud, happy lives in a body that's culturally feared and held up as wrong - that takes an incredible strength and self-confidence.

CB: You disagree with the majority of weight experts. They tell us that overweight is one of the leading causes of premature death, for instance from heart attacks, but also from diabetes and other diseases. Why do you disagree?

LB: I disagree because I have looked at the evidence. Reputable studies, published in well-respected, peer-reviewed journals, actually show that people in the "overweight" category live longer than those in the "normal" weight category.

CB: And what makes you sure that you are right and they are wrong?

LB: My experience from having worked closely with many obesity researchers who are more conventionally-minded than me is that they are so strongly mired in their assumptions, that they don't look at the evidence. Those that willingly engage, change their beliefs. The evidence is quite convincing.

CB: You said that weight increase and diabetes share common causes, in other words, that weight increase is a parallel outcome together with diabetes and not a cause of diabetes. Normally, high quality studies are controlled for such common causes. For instance, the effect of a sedentary lifestyle could be filtered out in a multiple regression statistics. Hasn't obesity been established as an independent cause of illness and premature death?

LB: Yes, weight sometimes plays a role in increased disease risk. I don't dismiss that entirely - rather what I am saying is that role is greatly blown out of proportion. While it is possible - and should be required - to control for a sedentary lifestyle and other counfounders, many studies don't. In the case of type 2 diabetes, studies show improvement can occur through lifestyle change, even in the absence of weight loss. It's much more productive to address the diabetes through lifestyle change. This is even more important when you consider that we don't have a proven way to accomplish weight loss - and how damaging the quest for weight loss can be.

CB: Let's come to another important point. What is right for some may be wrong for others. There are some studies on the "obesity paradox", as they call it. In patients suffering from various diseases, the obese have better survival chances. The same is true for persons older than sixty years. But what about children? Is it really okay for them to have a body mass index of thirty or more?

LB: All kids can benefit from good lifestyle habits - why do we have to pick on the fat kids?

CB: If people are fat and sick and if they lose weight and get cured, this could be a proof that fatness causes disease. Has there been any such outcome in a study?

LB: That seems like an impossible study to conduct. You would have to control to make sure that nothing changed other than their weight. They would have to be doing something differently to lose weight. For example, suppose they exercised more - you couldn't attribute the health improvement to the weight loss as it might have come from the activity changes.

I suppose you could look to the surgical studies to see the effects of weight loss without changing lifestyle factors. Gastric bypass surgery appears to reverse diabetes within days, before significant weight is lost, suggesting that it is not the weight loss that brings about the improvement, but probably some other factor (such as a change in the release of gut hormones).

There was also a liposuction study that examined weight loss in diabetic women. Despite the weight loss, their metabolic profile did not improve, including their fasting glucose and insulin levels or their insulin sensitivity.

CB: How much do they lose anyway, in the long run? What is the average weight loss five or ten years after the beginning of the fight against fat?

LB: All the long-term research shows that the majority of participants on diet and exercise programs regain ALL of the weight. There has been remarkably little long-term research on surgical outcomes, but even that is showing long-term weight regain, albeit much further down the line. And that's in addition to introducing a lot of "complications."

CB: I have the impression that body weight trends go to the extremes. Some gain more and more weight, others get thinner and thinner. Am I right? And where do you see the causes?

LB: Among thinner people, nothing has changed, not even by a few pounds. Move up the weight scale, and people are putting on a few pounds. Get to mid-range and people are just 6 or 7 pounds heavier than they were in 1991. It is only with the very heavy, at the extreme of weight, that there is a substantial increase in weight, about 25-30 pounds.

No doubt our lifestyle habits have changed during this time frame. Genetic differences result in people having varying degrees of susceptibility to weight gain - even under the same environmental conditions (meaning eating, activity and other habits).

CB: Any treatment should follow the rule "first do not harm". Does the war on obesity meet this rule?

LB: Sounds good to me. Seems clear its time to end the war, which we're clearly losing anyway. There's a antidote to the war on obesity, called "Health at Every Size" which supports people in engaging in healthy lifestyle habits as opposed to a primary focus in weight loss. I envision it as a peace movement.

I conduct research on Health at Every Size (HAES). The results show that women can make very dramatic improvements in health and well-being through adopting HAES. These results were particularly dramatic when the women in the Health at Every Size program were compared to others in a conventional weight loss program. Those in the weight loss program experienced the typical results - initial weight loss and health improvement - not sustained over time. And their self-esteem plummeted. This was in sharp contrast to the phenomenal improvements experienced by the women in the Health at Every Size program, who felt very much empowered.

CB: Thank you, Linda, for giving us a fresh view on a problem that only seems to be a problem because we make it a problem. I hope you'll help a lot of people to enjoy what they eat and to live healthy at every size.

LB: Thanks for the interest, Christian. It's important to be discussing these issues. It's been hard to give short responses to your questions. I have examined them all in a lot of depth. In fact, I'm just finishing a book on this topic. Health at Every Size: Finding Your Happy Weight, will be coming out in June 2008.

Linda Bacon's homepage
Health at Every Size

Photo credit: UC Davis

No comments: